After Google said they had achieved what quantum computing researchers had sought for years, a team of Chinese researchers now claim to have replicated the performance of Google's Sycamore quantum computer using traditional hardware.
In 2019, Google researchers claimed they had passed a milestone known as quantum supremacy when their quantum computer Sycamore performed in 200 seconds an abstruse calculation they said would tie up a supercomputer for 10,000 years.
Now, scientists in China have done the computation in a few hours with ordinary processors. A supercomputer, they say, could beat Sycamore outright.
"I think they are right that if they had access to a big enough supercomputer, they could have simulated the task in a matter of seconds," said researcher Scott Aaronson, a computer scientist at the University of Texas, Austin.
The team used a system comprised of 512 GPUs to complete the same calculation developed by Google to demonstrate it had passed the quantum supremacy milestone back in 2019.
The advance takes a bit of the shine off Google's claim, said Greg Kuperberg, a mathematician at the University of California, Davis.Still, the promise of quantum computing remains undimmed, the team said.
Sergio Boixo, principal scientist for Google Quantum AI, said in an email the Google team knew its edge might not hold for very long."In our 2019 paper, we said that classical algorithms would improve," he said. But, "we don't think this classical approach can keep up with quantum circuits in 2022 and beyond".
The "problem" Sycamore solved was designed to be hard for a conventional computer but as easy as possible for a quantum computer, which manipulates qubits that can be set to 0, 1 or any combination of 0 and 1 at the same time.